In its intended use, the mass air flow sensor has an O-ring circumscribing the sensing head which seals the mass air flow sensor in the mounting port through which the sensor head is inserted into an air flow passage whose mass air flow is to be measured. If this O-ring is missing, air will leak through the mounting port and will adversely affect the mass air flow measured by the mass air flow sensor. Current production techniques require a visual inspection of the mass air flow sensor to determine that an O-ring has been properly installed. With the automation of the mass air flow sensor production, a variety of test and calibration procedures which require calibrated air flows are automatically executed. The absence of the O-ring will result in improper calibration of the mass air flow sensor and cause the sensor to fail the required test.
To eliminate these problems, disclosed herein is a production line O-ring test apparatus capable of automatically and quickly detecting the absence of the O-ring on the mass air flow sensor.